Problem: Simplify the expression. $ (3r^{7}+4r^{2}) - ( 5r^{7}+r^{2}) - ( -4r^{5}-6r^{4}) $
Answer: Distribute any negative signs. $(3r^{7}+4r^{2}) + (-5r^{7}-r^{2}) + (4r^{5}+6r^{4})$ Since we are adding polynomials, we can simply remove the parentheses. $3r^{7}+4r^{2} - 5r^{7}-r^{2} + 4r^{5}+6r^{4}$ Identify like terms. $ {3 r^7} + \color{#9D38BD}{4 r^2} - {5 r^7} - \color{#9D38BD}{ r^2} + \color{#DF0030}{4 r^5} + {6 r^4} $ Combine like terms. $ { ( 3 -5 ) r^7} + \color{#DF0030}{ 4 r^5} + { 6 r^4} + \color{#9D38BD}{ r^2} $ Add the coefficients. $-2r^{7}+4r^{5}+6r^{4}+3r^{2}$